Methods for dry-cleaning fabrics commonly employ organic solvents which can readily dissolve or disperse soils such as water-insoluble substances, including greases, oily dirts and the like, and which exhibit low solvent boiling points, enabling easy recovery of the solvents.
The use of solvent-based dry-cleaning methods has, however, been primarily limited to commercial cleaning operations which employ expensive specialized equipment. Such equipment includes stills with condensers to contain vapors from the cleaning solvents, which are often toxic. As a result, to utilize such dry-cleaning processes, particularly to remove water-insoluble spots and/or stains from clothes, the user must bring the clothes to a specialized dry-cleaning establishment and pick up the cleaned clothes at a later date. This results in inconvenient expenditures of time in going to the dry-cleaner, waiting for the clothes to be properly cleaned, picking up the clothes, and dealing with damaged and lost articles of clothing. Moreover, articles of clothing from many different people are dry-cleaned with the same batch of solvent, which can result in malodorous residues.
A process for home dry-cleaning clothing is disclosed by S. Denissenko et al. in U.S. Pat. No. 4,336,024, wherein the soiled areas are pre-treated with a liquid cleaning composition. The clothing is then attached to an absorbent sheet and spun using the spin cycle of a washing machine, so that the cleaning composition and the soil are driven through the clothing and into the absorbent sheet. It is also disclosed that the absorbent sheet can be integrally sealed onto a plastic sheet, so that the clothing can be enclosed by the sheet while it is spun in a washing machine. Also, U.S. Pat. No. 5,238,587 issued to J. Smith et al., discloses a method for cleaning soiled fabric via the enclosure of the desired clothing in a bag with an added sheet impregnated with a gelled liquid cleaning composition. (The entire contents of U.S. Pat. No. 4,336,024 and U.S. Pat. No. 5,238,587 are incorporated herein by reference.)
However, these conventional methods for dry-cleaning contain high amounts of water as a component. High water level formulations tend to leave "water marks" after the spot or stain is removed from soiled fabrics, especially delicate fabrics such as 100% acetate, silk, rayon and blends of these fabrics. In fact, these delicate fabrics (especially acetate and rayon) will simply water stain from exposure to rain. To combat this problem, current professional dry cleaning methods use essentially anhydrous solvent systems based on perchloroethylene or hydrocarbon solvents, which are undesirable from an environmental standpoint. Such professional systems also contain detergents (usually about 1-3%) and a small amount of water (about 5%) to help the detergents work.
It is therefore an object of the invention to provide a dry-cleaning composition that contains no or only small amounts of water when compared to conventional dry-cleaning compositions.
It is an object of the invention to provide a dry-cleaning composition that contains polysulfonic acid as an essential ingredient.
It is an object of the invention to provide a dry-cleaning composition suitable for use in dry-cleaning delicate fabrics such as 100% acetate, silk, rayon and blends of these fabrics.
It is also an object of the invention to provide such a dry-cleaning composition that does not include solvents like perchloroethylene or other undesirable hydrocarbon solvents, such as those used commercially.
It is an object of the invention to provide methods of use therefor which can be conducted at home without having to take soiled or stale-smelling clothes to commercial cleaning establishments and incurring such inconveniences and disadvantages mentioned above.
Additional objects of the present invention will become readily apparent to persons skilled in the art from the following discussion.